An image can be formed on a paper sheet using a decolorable color material, which allows the paper sheet to be reused by decoloring the image. A decoloring device can decolor the decolorable color material by applying high temperature on the paper sheet. The decoloring device can start a decoloring operation in response to the paper sheet being disposed in a decoloring tray.
However, when the decoloring device operates, total power consumption of the decoloring device together with other devices may exceed an upper limit. If a power consumption value exceeds the upper limit in an environment where the decoloring device is installed, a power supply to a device including the decoloring device may malfunction.